Cam and wedge actuated wrench or pliers



Feb. 8, 1955 E. K JOHNSON 2,701,492

CAM AND WEDGE ACTUATED WRENCH OR PLIERS Filed July 17, 1953 United States Patent CAM AND WEDGE ACTUATED WRENCH OR PLIERS Ervin K. Johnson, Speers Ferry, Va.

Application July 17, 1953, Serial No. 368,647

7 Claims. (Cl. 81-78) This invention relates to a novel construction of wrench or plier type tool including a movable jaw actuated by the combination of a wedge and cam and wherein the Wedge is adjustable for accomplishing rough adjustments of the movable jaw and the cam is thereafter operated to complete closing of the jaw to a desired extent.

Another object of the invention is to provide a combination cam and wedge operated wrench or pliers which may be readily held and operated with one hand and wherein the movable jaw may be effectively maintained in a desired closed position by a normal gripping action on the wrench without risk of the movable jaw being forced away from a stationary jaw by a spreading action resulting from attempting to turn the wrench or pliers relatively to a nut or other similar element having a plurality of jaw engaging lands.

Still a further object of the invention is to provide a tool of the character described of extremely simple construction composed of a minimum number of parts which is capable of functioning efficiently as a wrench and of being operated and adjusted with the ease of a pair of liers. p Various other objects and advantages of the invention will hereinafter become more fully apparent from the following description of the drawing, illustrating a presently preferred embodiment thereof, and wherein:

Figure 1 is a side elevational view showing the wrench or pliers in an adjusted open position;

Figure 2 is an enlarged fragmentary longitudinal sectional view, partly in side elevation thereof, and

Figures 3 and 4 are cross sectional views of the tool taken substantially along planes as indicated by the lines 3-3 and 44, respectively, of Figure 1 Referring more specifically to the drawing, the combination wrench or pliers in its entirety is designated generally 6 and includes an elongated handle 7 which tapers in width toward an outer gripping end 8 thereof. The inner end of the handle 7 is provided with an extension 9 forming a continuation of a portion thereof located adjacent an outer longitudinal edge 10 of said handle. The inner side of the extension 9, which form s a stationary jaw, is recessed and toothed to provide a aw face 11 The handle 7 is of substantial width between its outer edge 10 and its inner edge 12, adjacent the stationary jaw 9, and said wide handle portion is recessed to provide a relatively deep groove or channel 13 which opens outwardly of the inner edge 12 and of the outer end of the handle 7, designated 14, between said inner edge 12 and the inner side or face 11 of the jaw 9. The groove or channel 13 extends inwardly from said inner edge 12 to adjacent the outer edge 10 of the handle 7 and from the forward end 14 to adjacent the restricted grip portion 8.

A movable jaw 15 is provided with a recessed toothed inner side 16 which faces toward the jaw face 11. The jaw 15 is provided with an extension 17 at one end thereof of reduced thickness forming a shank which extends through the forward edge 14 rearwardly into the slot 13. A pivot pin 18 extends loosely through the inner end of the shank 17 and is anchored at its ends to the handle member 7 near the closed bed of the slot 13. The shank 17 is of a thickness to swing freely in the slot 13 but to prevent any appreciable lateral swinging movement of the jaw 15 relatively to the stationary jaw 9.

A lever 19 has an end 20 of reduced thickness which extends into the forward end of the slot 13, remote to the jaw 9 and through portions of the forward edge 14 "ice and inner edge 12 of the handle member 7. A pivot pin 21 extends loosely through the lever end 20 and has its ends anchored in the handle member 7. The inner edge of the lever 19, near its opposite free end, is provided with a finger receiving recess 22, as seen in Figure 1. The outer edge of the lever end 20 is eccentrically disposed relatively to the pivot 21 to form a cam surface 23.

An elongated wedge block 24, which is tapered in width from end-to-end thereof, is disposed in the slot 13 between the jaw shank 17 and the cam surface 23 and has its tapered end extending outwardly toward or through the forward edge 14 of the handle member 7. The laterally enlarged inner end of the wedge block 24 is provided with an arcuate recess forming a socket 25 having a restricted end opening outwardly of the enlarged end of the wedge block.

A bar 26 of flat stock has notched or toothed edges, the teeth of which are staggered to form a thread 27. The bar 26 is provided with a head 28 at one end thereof which fits relatively snug in the socket 25. The bar 26 has a restricted neck 29 located adjacent the head 28 and which is sufficiently narrow to loosely fit the restricted open end of the socket 25 and to allow the head 28 to have a limited turning movement in the socket 25 and in directions coplanar with the wedge block 24. The wedge block 24 and the bar 26 are of a thickness to fit relatively snug in the slot 13 and so that the handle member portions defining the sides of the slot will prevent the wedge block 24 or bar 26 from lateral movement one relatively to the other, to thus maintain the head 28 in engagement with the socket 25. It will thus be apparent that the head must be fitted into the socket 25 before the wedge block 24 and bar 26 are applied to the slot 13.

The body member portions forming the side walls of the slot 13 are provided with corresponding laterally elongated openings 30 which are located more remote to the front edge 14 than the pivot pin 18. A nut 31 is loosely disposed in the openings 30 and in threaded engagement with the thread 27 of the bar 26. The bar 26 is inserted or threaded through the nut 31 in a direction toward the grip 8 so that its head 28 and the wedge block 24 will be disposed between said nut and said front edge 14. It will be readily apparent that the threaded bar 26 supports the nut in the openings 30.

An elongated leaf spring 32 has a portion located adjacent one end thereof which extends from the slot 13 outwardly thereof through an opening 33 in the handle member 7 between the slot 13 and the outer edge 14. The end of the spring 32 which extends outwardly through the opening 33 is provided with a reversed bend so that a terminal portion 34 thereof, located adjacent the opening 33, will seat in a recess or socket 35 of the handle member 7 which opens through said outer edge 10. The remainder of the spring 32 extends from the inner end of the opening 33 forwardly through the slot 13 between the closed bed portion 36 of the slot 13 and the shank 17. The free end of the spring 32 is defined by a rounded portion 37 the convex side of which bears resiliently and slidably against the inner edge of the shank 17 and movable jaw 15 and yieldably urges said jaw and shank to swing on the pivot 18 counterclockwise as seen in Figures 1 and 2 and away from the stationary jaw 9. Swinging movement of the jaw 15 and shank 17 away from the jaw 9 is limited by engagement of the shank with the wedge block 24 and engagement of said wedge block with the cam surface 23.

An initial rough adjustment of the open and closed positions of the movable jaw 15 is accomplished by manually turning the nut 31. If the nut 31 is turned in one direction one side thereof will bear against the inwardly curved walls of the openings 30 which are located remote to the wedge block 24 and the threaded bar 26 will be displaced or fed through the nut 31 toward the forward edge 14, thereby displacing the wedge block 24 in the same direction for causing it to rock the movable jaw 15 and shank 17 toward the stationary jaw 9. If the nut 31 is rotated in the other direction its opposite side will bear against the other inwardly curved edges of the openings 30 which are located nearest the front edge 14 for displacing the bar 26 away from said edge 14 and for aromas causing the bar to exert a pull on the wedge block 24 for moving said wedge block in the same direction to allow the shank 17 and jaw 15 to be swung by the spring 32 counterclockwise as seen in Figures 1 and 2, toward a further opened position. After a proper rough adjustment of the movable jaw 15 has thus been accomplished by operation of the nut 31, the grip portion 8 and the part of the handle member located adjacent thereto is grasped in either hand with the outer edge bearing against the palm of the hand so that the fingers may grasp the lever 19, in the same manner that one lever arm of a pair of pliers is engaged by the fingers. The tool 6 is positioned so that an element to be turned, such as a nut or bolt, not shown, is disposed between the jaw faces 11 and 16. The lever 19 is then moved by the fingers by a gripping action counterclockwise on its pivot 21 toward the handle grip 8 and until the lever 19 is disposed nearly parallel to the longitudinal axis of the handle member 7, as illustrated in dotted lines of Figure 2, at which time the tool may be gripped by the grip portion 8 and lever 19. As the lever 19 is swung counterclockwise from its full line position of Figure 2 to its dotted line position thereof, the portion of the cam surface 23 located most remote to the pivot 21 will move into position between said pivot and the wedge block 24 as the lever 19 approaches its dotted line position of Figure 2. Thus, the wedge block 24 will be rocked clockwise about the head 28 to swing from its full line to its dotted line position of Figure 2 and for swinging the shank 17 and jaw 15 in the same direction from their full line to their dotted line positions. The jaw 15 is in its closed position and dotted line position of Figure 2 according to the adjustment accomplished by the nut 31 for gripping an element between the jaw faces 11 and 16. Furthermore, the cam portion 23 disposed most remote to the pivot 21 is moved slightly across a dead center position extending from the pivot pin 21 to the nearest part of the wedge block 24 so that pressure tending to swing the jaw 15 toward an open position will not tend to swing the lever 19 back to its released position of Figure 1.

With the lever 19 in its dotted line position of Figure 2, the tool 6 will effectively function as a wrench and the movable jaw 15 thereof will not be cammed toward an open position by resistance to rotation of the element engaged between the jaws, as is common with the use of pliers. However, the tool 6 may be opened and closed with the ease of pliers as it is only necessary to engage a finger of the hand grasping the tool in the finger recess 22 for swinging the lever 19 clockwise away from the grip 8 toward its released position of Figure 1. As the lever 19 swings toward its position of Figure 1, the spring 32 will swing the jaw 15 away from the jaw 9 to an open position so that the tool will be released from the element previously engaged thereby preparatory to taking another grip on the element or to engaging another element to be turned, and which is readily accomplished, as previously described, by merely swinging the lever 19 back to its dotted line position of Figure 2 after the element to be engaged is disposed between the jaw faces 11 and 16.

Various modifications and changes are contemplated and may obviously be resorted to, without departing from the spirit or scope of the invention as hereinafter defined by the appended claims.

I claim as my invention:

1. A combination pliers or wrench type tool comprising an elongated handle member having a stationary jaw at one end thereof, a movable jaw pivotally connected to the handle member at a point longitudinally and lateral- 1y spaced from said stationary jaw and mounted for swinging movement toward and away from the stationary jaw and disposed in a plane coplanar with the stationary jaw, a lever pivotally connected adjacent one end thereof to the handle member in longitudinally and laterally spaced relationship to the pivot of the movable jaw, said lever having a cam surface eccentrically disposed relatively to the pivot thereof, said movable jaw being disposed between said lever pivot and the stationary jaw, a wedge block extending between said cam surface and an adjacent longitudinal edge of the movable jaw, and means swingably mounting an end of the wedge block, located adjacent the movable jaw pivot, for swinging movement of the wedge block toward and away from the movable jaw and cam surface, said means being operable for moving the wedge block longitudinally for positioning portions thereof of different thicknesses between the movable jaw and cam surface, and said lever being swingable to cause the cam surface thereof by engagement with a longitudinal edge of the wedge block to swing said wedge block and movable jaw for moving the movable jaw toward the stationary jaw.

2. A tool as in claim 1, said stationary jaw forming an extension of said handle member end and a continuation of an outer longitudinal edge thereof, said handle member being relatively wide adjacent said end and having a slot formed therein and opening outwardly of said handle member end and outwardly of an inner longitudinal edge of the handle member, the pivoted ends of said movable jaw and lever being disposed in said slot, said wedge block and a portion of said wedge block actuating means being mounted in the slot.

3. A tool as in claim 2, said actuating means comprising a fiat sided feed screw slidably and nonrotatably disposed in said slot and a nut threadedly engaging said feed screw, said handle member having portions defining side walls of the slot and provided with aligned openings through which portions of said nut extend, said nut being maintained by the screw in said openings and being retained against longitudinal movement relatively to the handle member by said openings whereby the exposed portions of said nut are manually engageable for turning the nut to move the screw and wedge block longitudinally of the handle member, one end of said screw being pivotally connected to an enlarged end of the wedge block.

4. A tool as in claim 3, said wedge block having fiat opposite sides fitting relatively snug between the handle member walls and having a socket opening outwardly of said enlarged end, said screw having a head engaging in said socket and combining therewith to form the pivotal connection between the wedge block and screw, said head being retained in engagemeent with the socket by the handle member walls.

5. A tool as in claim 1, said handle member having a slotted portion containing the pivoted ends of the movable jaw and lever, a portion of said actuating means and said wedge block, and a leaf spring having one end anchored to the handle member and an opposite end engaging the movable jaw and disposed between said movable jaw and stationary jaw and urging said movable jaw to swing away from the stationary jaw, said spring being disposed in and longitudinally of said slot.

6. A tool as in claim 1, spring means urging said movable jaw to swing away from the stationary jaw, said handle member having an opposite end forming a grip portion, and said lever having an opposite free end swingable toward and to a position adjacent said grip portion whereby said cam surface is moved to actuate the wedge block and movable jaw for swinging the movable jaw toward the stationary jaw.

7. A tool as in claim 6, the portion of said cam surface disposed most remote from the lever pivot moving across and to beyond the wedge block portion located most adjacent the lever pivot as the free end of the lever approaches said grip portion for releasably locking said movable jaw in a closed posltion.

References Cited in the file of this patent UNITED STATES PATENTS 174,142 Martin Feb. 29, 1876 433,978 Corning et a1. Aug. 12, 1890 571,287 Ryder Nov. 10, 1896 574,487 Kapka Jan. 5, 1897 805,792 Hadden Nov. 28, 1905 1,094,400 Burgess Apr. 21, 1914 2,420,020 Snell May 6, 1947 FOREIGN PATENTS 287,541 Italy July 25, 1931 

